One sore point seems to remain : Apple HomeKit certification apparently not only applies to the Hue bridge but also to the lamps connected to the Hue Bridge :

Before the 1.11 software update, a bug in the Philips Hue system allowed some non-Apple HomeKit certified lights to work with Apple HomeKit. Our 1.11 software update removed the bug with the result that non-Apple HomeKit certified lights no longer work with Apple HomeKit. This remains the case.

The LivingWhites adapter doesn’t really have many surprises. The only two notable things are that the entire high voltage side is from ST parts (VIPER16 , 2 x 14NM65N , ST1S10 ) and the other surprise is the other LED not in the manual.